Tunnel-oven.



C. DRESSLER.

` TUNNEL om. APPLICATION HLED-1ULY 28,19l?.

Patented Nov, 26, 1918.

3 SHEETS-SHEET l F v. vrbx MGI MN VIL C. DRESSLER.

TUNNEL OVEN.

APPLICATION FILED IuLY 28. IsII.

3 SHEETS-SHEET 2.

Putent'cd Nm'. 26, 12H8.

3 SHEETS-SHI rT 3.

D @TAMS PJEN CONRAD DRESSLER, YOF IVJIARZO'W, ENGLAND.

To all 'wwm it may concern: I Y

Be it known that l, CONRAD Dmcssnmi, a. subject of the King of Great Britain and Ireland. residing at Marlow, in the. county of Buckingham, England, have invented Improvements in or l'lelatintgr to Tunnel- Ovens, ofy which the following is a specificc tion. t

ln tunnel-ovens of the kind in which gaseous liquid or like fuel (hereinafter referred to generally as g'as) is burnt in independent combustion chambers arranged longitudinally ofthe oven,`as described in the specifications of-,.former Letters Patent granted t0 me,a No. 1023628, dated April 16th, 1912, No. 1116036, dated November 3rd, 41910, and No. 1170l28, dated February lst, '1916, it has been customary to introduce the gas and air practically at one point only inthe length of each combustion chamber so that'the hottest part of the oven occupies only a short portion of the length of the oven, loc-ated usually near the center of the length of the oven. As a result., the goods, which travel slowly and continuously through the oven, are subject to the maxi `n1um temperature for only a c0n'1parati.'ely

short time. Itis however desirable in some cases, as for instance when tiring massive pieces of sanitary ware or other goods re` quiring very high temperatures or ,good heat distribution therein, tha/t the goods ,shall be exposed to the maximum temper-atae, or to a high temperature `which maybe lbetween the maximum and minimum temperatures of the oven, for a prolonged period, or that they shall be subjected alternately 4to a high y temperature, then to a lower temperature and allyheated up to the Letters Patent granted, to me, No,

derived from a, given then to a high temperature in succession, or to a repetition of high, lower-'and high tem` peratures, so that they shall undergo a heat soaking treatment instead of. being gradumaximum temperature and then gradually subjected to any prolonged heating at the maximum-br at any one temperature.

vfx1-'tunnel ovens as described in, further 1,225,318, provision is made for regulatably introducing ras and airat length of the combustion chamber, Yith the obj ect of producing temperature regions differing between'themselves but each more or less uniform throughout a "predetermined length of the combustion chamber, the heat' burner being supple- Specification of Letters latent.

,mingling otl cooled .Without being different pointsalong the,

Patented Nov. 26, i918. Serial No. 183,318.

mented by that produced by another or other burner or burners rearward thereof. vThe the products of conibustion from forward burners with the newly entering gas and air at that or those in rear thereof by diluting the latter prevents the temperature of combustion rising t0 as high n point as it otherwise might, successive burners accordingly losing' in effectiveness correspondingly with the extent of dilution of their gas and air by the.inertproducts of combustion from burners forward thereof.

Now the present invention has for its object, to construct and operate tunnelovens having,r longitudinally arranged combustion chambers as referred to, with successive inlets for gas and air rearward one of another whereby more effective combustion is ob tained at the successive burners, better reg'- ulatlon secured of' the temperature of any given zone and attainment of a higher tem! perature in a maximum temperature Zone rendered practicable. The. combustions are so regulated that a curve representing the temperature 'at various parts along the oven shallihave a prolonged raised portion more nearly approaching a straight 'line than is attainable with the said referred to tunnel ovens. l i

By .such means goods while traveling' continuously through the oven can be subjected for a prolonged periodtoa substantially uniform-high temperature that may be the maximum temperature of the oven, or involve zones of substantially uniform maximum temperature separated by one or more like zones of low'er but still high temperature.

For this purpose accordingl tothe present invention each combustion. chamber is provided atseparated points along its length with two or more combustion Zones each comprising a combustion space with inlets forgas and air and hereinafter referred to collectively, for brevity, as a burner in such manner lthat the combustion spaces or zones in the longitudinally extending combustion chamber shall be independent of each other so that the gassupplied to each of them can be l`burnt by pure air and therefore under tg? most favorable and eieient conditions. is system of 'workingyields short. llames or zones of heat `0f high long llames oflower intensity ohtainedvwith the formersystem of working. Both systems however enabley soakingfones 'to be intensity instead of I 1 MPG the the products of combustionfroin that burner an advanced part a1 ot the chamber.

Qr, as'shown in Fig. 10, a tube or Conduit m may be arranged to extend into and 'partly through the combustion chamber fz to'supply .7o air to the gals inlet'rl of the forward burner ne cour and protect.- the resulting 'flame troni the, superposed products of combustion flowing over, around it or reiraetor, or past it from the rear burner all.

i3 materie.; may adv he car l'n the furtherv modified construction '15 ooruntluni o? use me '-a, stiperposed shown in Fig. 1l, theilconjlhstion chamber a 55 or combustion zones and del J sections heine; isngee AWhere necessary, as is provided, adjacent to and beliindthe' torshown at of in n', 3, to provide sulheient ward burner a', with a trelfnsverse wall 'a di# strength joint at i between the top of viding it into two main longitudinal parts 1;, the pm tion and top o2 of the ooinbuso and a* and with an external bypass flue or 8o tion n r may edvantapassage'a" that connects the rearward porgef' with. Silj/ olaf. which will tion a4 lto the forward portion o3 at a point t allow movement; due to a where the products ot' combustion from when parts. The partithe rear burner (l1 will not aect the combus- Connection 'with the coinhustion of the gas atithe forward burner a. S5 may not at, all times be pen The by-pass flue or passage a may be ar-v f hy this will not seriously ranged in different ways; in the example aieet the poration ot' the. burners. t shown in Fig. 1l, it is arranged at the outer According to modified constructions, side of thecoxnbustion chamber and` extends 25 shown in '1 5, the longitudinal partition into the adjacentside wall (if of the oven. So o may uit l werd onl7 from the gas inln the arrangements hereinbefore deiet of ofthe n "ard hamer and at this point scribed where the ombust-ion ot' ,gas by air he eonilfained Y a transverse partition Zia to at thefrward burner is unaffected by prodforin lon ral eoing'iartment o closed at ucts of combustion coming from the rear 3@ the 1 1ere it will also he provided burner, themaxinumx heat under the Qontli- 95 with an a irte at l'the top. tion of supply of air and gas' obtaining, will instead ot using a longitudinalVertical he attained at Ieach burner, and a prolonged partition o as shown in Figs. 2 and 3, one heat/int1r zone of a more 'or less substantially or more .partitions may also he arranged uniformly high temperature for the goods to 35 horizontallpf', if desired, the zas and airA intravel through, will. notwithstanding that 100 lets being' suitably arranged to meet the altfhe'lmrners are displaced longitudinally, be tered positions of the compartments. f obtained by reason of the hot air which, as Figs, 'i and 8 show a construction of shown by the arrows in Fig. 3, is caused to combustion chamber of this hind provided How, by convection, under, around and over n with a number of separate burners or comthe combustion chamber and downward N5 bastion zones t' arranged in tandem with 'through the heating' zoneglt" between the the top walisa thereof arranged horizontally combustion chambers through which the at different levels, step wise, and at one side goods are traveling, as described` in the said of a l'ongiiiulinal vertical partition t. Each former specifications. 45 burner or combustiisn r has at one end, It will be understood that in some Cases 110 an inlet al., at the bottoni, for gas, and above the burners may be arranged in series so it an end inlet a iorairfroin a hot air supply that. thel products of combustion mixed compartment u arranged at one side of the nxore or less with air, coming from the rear partition At the other and, each burner burner will pass through the combustion 5o or combustion Zone r is in coinniunication space of the forward burner to which airs 115 through a lateral outlet r with a coinpartand gas are separately delivered. ln this ment w arranged at the other side or" the parsystem of working` instead of obtaining tition and which serves to receive the hot. short flames or zones of heat of high .ihproducts of co ustion from all tlieburners tensity, as ith the system o working iter them into hereinbefore Ldescribed, long llames of 12@ the forward portion al ot he con/:bustina lower intensity will be obtained. This Y chamber a or fluo. system of working Will not be so economiin the modified construction shown in Fig. cal in fuel, or be so easily controlled, as t), nach :onibustion chamber is provided at the first system described. Both systems ao, the-part thereoi where the forwart burner (Z will however enable soaking zones to he oh-v 125 is located, with a centrally arranged tube or tained suitable for. different classes of Work. conduit i: ot"reiraetory material through Figa/12 shows, in Vertical section, one' arwhich the products of combustion from the 'angement designed to Werken the second rear burner di can flow past the Combustion system lreferred. to, d' and e being the gas @s zone of the forward burner and mingle with and air inlets of the-ato ward 'hgirn-er and lso Lai Whfekfn *131e wir 21a supplied through l pipi? e having a number of Oules (n 111 m esci; of zhe h un ndependem; of each @they so that prod'ucs ranged combustfim chamber nwnf :a hi- 3M mxggh @md pzw @ning means, arranged 

